Hi there,
So FWIW, I tried the Nordic LBS demo (posted here) with the Xiao Nrf52840 Sense. I used 2.6.1 through 2.8.0., No issues with builds or Jlink everything builds and Advertises.
I did have to install the tool chain for 2.8.0 and it updated some Zephyr stuff , restarted and rebooted. ALL Systems GO!
HTH
GL

